Metal enclosed switchgear having circuit interrupter means mounted on the door and connected in series and interlocked with switch blade means



y 8, 1968 a. G. SCHOCKELT 3,385,938

WITCHGEAR HAVING CIRCUIT INTERRUPTER METAL ENCLOSED S MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS l4 Sheets-Sheet 1 Filed May 23. 1966 May 28, 1968 s. e. SCHOCKELT METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS Filed May 23, 1966 14 Sheets-Sheet 2 //X////Z/////////////V/lfl G. G. SCHOCKELT May 28, 1968 3,385,938

METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS Filed May 23. 1966 14 Sheets-Sheet 5 y 8, 1968 G. G. SCHOCKELT 3,335,933

METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS l4 Sheets-Sheet 4 May 28, 1968 s. G. SCHOCKELT 3,385,938

METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS Filed May 23, 1966 14 Sheets-Sheet 5 Q 2 y 8, 68 e. G. SCHOCKELT METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS l4 Sheets-Sheet 6 Filed May 23, 1966 y 3, 968 6. cs. SCHOCKELT 3,385,938

METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED .IN

SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS Filed May 23. 1966 14 Sheets-Sheet y 8, 1968 e. G. SCHOCKELT 3,385,938

METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUP-TER MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS Filed May 23, 1966 14 Sheets-Sheet 8 7 3,385,938 EAR HAVING cmcuxw INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED IN May 28, 1968 G. e. SCHOCKELT METAL ENCLOSED SWITCHG SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS Filed May 25, 1966 14 Sheets-Sheet 9 l5 -4 P- 2 I 3,385,938 UPTER May 28, 1968 G. e SCHOCKELT METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERR MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS l4 Sheets-Sheet 10 FL 15.

Filed May 23, 1966 May 28, 1968 G. G. SCHOCKELT 3,3 5, 3

METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS l4 Sheets-Sheet 11 Filed May 23, 1966 3,385,938 UPTER y 1968 e. e. SCHOCKELT METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERR MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS l4 Sheets-$heet 1:"; ig-

Filed May 26, 1966 TER y 68 5. G. SCHOCKELT METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUP MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS l4 Sheets-Sheet 1-3 Filed May 23, 1966 M y 28, 1968 G. G. SCHOCKELT 3,385,938

METAL ENCLOSED SWITCHGEAR HAVING CIRCUIT INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH I SWITCH BLADE MEANS Filed May 23, 1966 l4 sheetsheet 14. I .Elg. 36.

United States Patent METAL ENCLOSED SWITCHGEAR HAVING 481R- CUI'I INTERRUPTER MEANS MOUNTED ON THE DOOR AND CONNECTED IN SERIES AND INTERLOCKED WITH SWITCH BLADE MEANS Guenter G. Schockelt, Skokie, IlL, assignor to S.C. Electric Company, Chicago, Ill., a corporation of Deiaware Filed May 23, 1966, Ser. No. 558,165 31 Claims. (U. 200-50) ABSTRACT OF THE DISQLOSURE Circuit interrupter means on a door of metal enclosed switchgear is connected in series with switch blade means interlocked with the door which can be opened only when the switch blade means is in open position.

This invention relates to metal enclosed switchgear. It constitutes an improvement over the metal clad switchgear shown in US. Beebe et a1. Patent 3,055,996 issued Sept, 25, 1962.

Among the objects of this invention are: To mount circuit interrupter means such as one or more fuses on a door of a metallic housing of compact design and arrangement for connection in series with one or more switch blades in the housing and to interlock the door and the switch blade or blades to permit opening of the door and making accessible the circuit interrupter means only when the switch blade or blades are in the open position; to make the circuit interrupter means, such as the fuses, so accessible that they can be removed and replaced without requiring the use of special fuse handling tools; to provide for manually operating latch means for the door and to interlock this latch means with the switch blade or blades; to mount the switch blade or blades on a rotatable shaft having a locking cam with which a locking lever cooperates and to interconnect the locking lever with a pawl that cooperates with latch means on the door; to interlock the door and the switch blade operating means thereby requiring that the latter occupy a predetermined position before the door can be opened and access can be had to fuses mounted on the door; to mount the switch blade or blades for rotation about a horizontal axis with the door carrying the fuses hinged about a vertical axis in one L embodiment and about a horizontal axis in another embodiment; to employ circuit interrupter means in series with each switch blade for opening the circuit; to interpose movable and stationary insulating barriers between the fuse or fuses on the door and the switch blade or blades in the housing with registering openings therein through which connection is made therebetween and which openings are closed on opening of the door; to mount the movable barrier for horizontal translatory movement in one embodiment and for vertical translatory movement in another embodiment; to mount both the fuses and the separable contact circuit interrupter means on the door whereby they are deenergized and readily accessible when the door is opened; to provide for manually discharging energy stored in a spring operator where this action is required under certain operating conditions; in a compact fuse and switch design of the kind herein disclosed to provide for direct interlocking action between the fuses and the switch blades, between a handle for opening the door and the switch blades, and between the door handle and the switch blade operating mechanism; and to permit opening the door to afford access to the fuse and switch containing housing only after the switch blades have been moved to their open position and the switch blade spring operating mechanism has been discharged.

3,385,938 Patented May 28, 1968 In the drawings: FIG. 1 is a view, in front elevation, of a cabinet for housing a disconnecting switch and fuse assembly. FIG. 2 is a view, somewhat diagrammatic in character, and taken generally along the line 22 of FIG. 1 to show the relation of the parts with the switch closed, the operating handle up and the door handle locked and in another part showing the relationship of the switch locking cam and the switch blade means to one of the fuses mounted on the door. FIG. 3 is a vertical sectional view, at an enlarged scale, taken generally along' the line 33 of FIG. 1. FIG. 4 is a view, somewhat diagrammatic in character, and showing the relation of the parts with the switch open, the operating handle down, the spring mechanism discharged and the door handle free to move. FIG. 5 is a view, similar to FIG. 4, showing the relation of the parts with the switch locked open, the operating handle locked in the mechanism discharged position, and the door handle in the open position. FIG. 6 is a vertical sectional view taken generally along the line 6-6 of FIG. 1. FIG. 7 is a top plan view, at an enlarged scale, of one of the switch blade means shown in FIG. 6 in contact engagement with the upper contact finger of the fuse at one end and in engagement with the contact portion of the metallic adapter for the circuit interrupter means at the other end. FIG. 8 is a top plan view of the rotatable elongated porcelain insulator shown in FIG. 6 with the switch blade means mounted thereon, certain parts being shown in section. FIG. 9 is a vertical sectional view, at an enlarged scale, taken generally along the line 99 of FIG. 8 and looking from left to right. FIG. 10 is a view, in end elevation, of the switch blade assembly shown in FIG. 8 looking from right to left. FIG. 11 is a horizontal sectional View, at a slightly enlarged scale, and taken generally along the line 1111 of FIG. 6. FIG. 12 is a vertical sectional view taken generally along the line 12-12 of FIG. 11. FIG. 13 is a vertical sectional view, at a slightly enlarged scale, taken generally along the line 1313 of FIG. 1 with the operating handle shown by full lines in the switch open mechanism discharge position and by broken lines in the switch closed position. FIG. 14 is a view, in front elevation, and at an enlarged scale of the switch operating mechanism shown in FIG. 1, certain parts being broken away and other parts being shown in section. FIG. 15 is a vertical sectional view taken generally along the line 15- 15 of FIG. 14. FIG. 16 is an elevational view of the locking cam for the switch handle. FIG. 17 is an elevational view of the switch mechanism position indicator. FIG. 18 is an elevational view of the mechanism toggle lever. FIG. 19 is an elevational view of the mechanism cam. FIG. 20 is an elevational view of the stop lever assembly. FIG. 21 is a vertical sectional view taken generally along the line 2121 of FIG. 14. FIG. 22 is an elevational view of the operating lever. FIG. 23 is an elevational view of the toggle lever member having switch opening and closing arms. FIGS. 24, 25, 26, 27, 28 and 29 are views showing the different operating positions of the mechanism toggle lever, switch and mechanism position indicator and the mechanism cam. FIGS. 30, 31, 32 and 33 are views showing different operating positions of the switch operating handle interlock mechanism and the arrangement for manual discharge of the stored energy in the operating spring. FIG. 34 is a view, in side elevation, of the coupling lever cam, the coupling lever and the connecting pin therefor in disassembled relation. FIG. 35 is a vertical sectional view of a metallic closure having an alternate form of disconnecting switch and fuse with the fuse or fuses mounted on a door that is hinged about its horizontal axis. FIG. 36 is a vertical sectional view of still another embodiment of this invention in which both the fuse and the separable contact circuit interrupter are mounted on the door for movement therewith to the open position.

In FIG. 1 the reference character designates, generally, a metallic enclosure for switch gear. It includes a top connecting box 11 having therebelow a metallic circuit interrupting apparatus housing, indicated at 12, that is mounted on a bottom connecting box 13. These enclosures are formed preferably of sheet metal. The top and bottom connecting boxes 11 and 13 are provided for receiving conductor cables or bus bars for the purpose of making connections to and from the circuit interrupting apparatus mounted in the metallic housing 12. They may be of various heights and interchangeable with each other. The metallic housing 12 includes a front wall 14, a left side wall 15, a right side wall 16, and a rear wall 17, FIG. 6. The top connecting box 11 includes a topwall 18 and the bottom connecting box 13 includes a bottom wall 19 both of which are provided with suitable openings for the conductors, cables, bus bars, etc., as may be required. The top and bottom of the metallic housing 12 are open to permit the necessary connections to the circuit devices mounted therein.

The front wall 14 has mounted therein a door 22 that is arranged to rotate about a vertical axis. The door 22 includes upper and lower hinge extensions 23 and 24. Also, the door 22 is provided with a recess 25, FIGS. 1 and 2, in which a door handle 26 is mounted. In the closed and locked position of the door 22, the door handle 26 is located wholly within the recess 25 and no part of it extends beyond the surface of the door 22. The door handle 26 includes an upstanding flange 27 to facilitate its being gripped by the fingers of the hand of an operator. At its upper end the door handle 26 is mounted for rotation with a door handle shaft 28 that is journaled in the side walls of the door 22 defining the recess 25. A torsion spring (not shown) surrounds the shaft 28 and acts in a direction to bias the door handle 26 to the non-operated position shown in FIG. 1. A locking loop 29 extends through an opening 30 in the door handle 26 to receive a padlock for the purpose of preventing unauthorized operation.

Along the right side of the metallic housing 12 there is provided a recessed operating mechanism support 31 which includes overcenter spring means, indicated generally at 32 and described in detail hereinafter. A manually operable handle 33 is employed for operating the overcenter spring means 32 and it has a hand grip 34 to permit manual operation. In the upper and lower positions the manually operable handle 33 is Wholly below the surface of the front wall 14. Likewise, the recessed operating mechanism support 31 and overcenter spring means 32 do not extend beyond the surface of the front wall 14.

As shown in FIGS. 1-5, manually operable door latch means 37 are employed in conjunction with the door handle 26 for controlling the opening of the door 22. As will appear hereinafter various interlocking mechanisms cooperate with the door handle 26 to prevent its movement to the unlocked position unless circuit switching apparatus in the metallic housing 12 occupies such position that it is safe for the operator to open the door 22. This is essential since relatively unskilled operators are likely to have access to the metallic housing 12. In accordance with this invention, for normal operation, it is not possible for the unskilled person who has access only to the metallic housing 12 by opening the door 22 to come into contact with any energized circuit parts.

The manually operable door latch means 37 includes a vertically movable latch bar 38 which is provided with .vertical slots 39 through which pins 46 extend from a door flange 41. Latch hooks 42 extend inwardly from the latch 46 is formed integrally with the door handle 26 and it can'ies a circular boss 47 that is positioned between the outstanding flanges of L-shaped brackets 48, one of which is shown in FIG. 3. On rotation of the door handle 26, when it is free to rotate, the latch bar 38 is moved downwardly from the position shown in FIG. 2 to the unlatched position shown in FIG. 5. Onreverse rotation of the door handle 26, the latch bar 38 is moved upwardly to the latched position.

For interlocking the operation of the door handle 26 with the circuit switchingv apparatus in the metallic housing 12, the latch arm 46 carries a detent 49 at its distal end that is provided with faces 56 and 51 which are arranged to be juxtaposed to faces 52 and 53 on a pawl 54 with the detent 49 being arranged to enter a notch 55 therein. The pawl 54 is pivoted on a pin 56 which extends from the side wall 15 and a torsion spring 57 is employed for biasing it in a clockwise direction as Viewed in FIG. 2. The torsion spring 57 reacts between the pawl 54 and a pin 58 which extends from the side wall 15.

It is desirable to prevent opening of the door 22 unless the manually operable handle 33 is in the lower position in the recessed operating mechanism support 31 in contradistinction to the upper position shown in FIG. 1. Also, it is desirable that it be possible to open the door 22 only when switch blade means, to be described, in the metallic housing 12 occupies the open position. This control is effected by positioning the pawl 54 under the control of the position of the manually operable handle 33 and of the switch blade means. FIG. 2 shows the manually operable handle 33 in the upper position and the switch blade means in the closed position. The location of the pawl 54 then is such that its face 53 is juxtaposed to face 51 on the detent 49 thereby making it impossible to rotate the door handle 26 in a counterclockwise direction to move the latch bar 38 downwardly and unlatch the door 22. For this purpose the pawl 54 is provided at one end with cable fastening means 61 to which a control cable 62 is secured intermediate its ends. One end of the control cable 62 extends through a stationary sleeve 63 to cable fastening means 64 carried at the distal end of a locking lever 65, FIG. 14. It will be understood that the showing in FIG. 2, as well as the showing in FIGS. 4 and 5, is somewhat diagrammatic in character and that, because of the flexibility of the control cable 62 and stationary sleeve 63, it is possible to locate the parts associated therewith in different planes from the plane of the drawing representing the relationship. The locking lever 65 is pivoted at 66 on the recessed operating mechanism support 31 and it carries a circular pin 67 that is arranged to ride on periphery 68 of a handle locking cam 69 that is arranged to rotate with the manually operable handle 33. The handle locking cam 69 has a notch 70 one side of which is formed by a shoulder 71 for receiving the circular pin 67 as seen in FIGS. 4 and 5. When the manually operable handle 33 is rotated to the lower position represented in FIGS. 4 and 5, it, together with the torsion spring 57 operating through the control cable 62, rotates the locking lever 65 to position the circular pin 67 in the notch 76. In this position the handle locking cam 69 is p evented from rotating and, a long as the door 22 remains open and the pawl 54 remains in the position shown in FIGS. 4 and 5, it is not possible to move the manually operable handle 33 from its lower position.

The control cable 62 extends from the cable fastening means 61 through another. stationary sleeve 72 and is secured by cable fastening means 73 to one end of a locking lever 74 that is pivoted at 75 on the side wall 15 as shown in FIG. 8. The other end '76 of the locking lever 74 is arranged to engage periphery 77 of a switch locking cam 78. A notch 75 is provided in the switch locking cam 78 having a shoulder 80 for receiving the end 76 as shown in FIGS. 4 and 5 which show the position of the switch locking cam 78 when the switch blade means occupies the open position. Particularly in FIG. 5 it will be observed that the end 76 is juxtaposed to the shoulder 80 and thus prevents rotation of the switch locking cam 78 and the switch blade means rotatable therewith as long as the pawl 54 remains in the position shown in FIG. 5. FIG. 4 shows an intermediate position in which the switch locking cam 78 is in the switch open position while the handle locking cam 69 and the manually operable handle 33 are being rotated to the lowermost position of the latter. In FIG. 4 the circular pin 67 is shown as entering the slot 70. Because face on detent 49 opposes faces 52 on pawl 54, the pawl 54 cannot rotate. When the manually operable handle 33 occupies the position shown in FIG. 2, the switch blade means is closed and the locking levers and 74 hold the pawl 54 in the position there shown with the face 53 opposite face 51 thereby making it impossible to move the door handle 26 to operate the latch bar 38 and unlock the door 22.

As shown in FIG. 6 the circuit interrupting apparatus within the metallic housing 12 includes one or more fuses, shown generally at 85, and mounted on the door 22 so that, when it is opened, they are readily accessible to the operator for replacing them. The fuse may be of any suitable type such as the fuse shown in US. Lindell Patent 3,230,331, issued Jan. 18, 1966. However, other fuse constructions, such as current limiting fuses, can be employed. For single phase operation only one fuse 83 is mounted on the door 22 and it has switch blade means and a circuit interrupter therefor. A larger number, for example three fuses 85, can be employed in conjunction with a three phase circuit. The fuse 85 includes upper and lower fuse terminals 86 and 87 from which upper and lower contact fingers 88 and 89 extend. As shown in FIG. 7 the upper contact finger 88 is a vertical bladelike two part member which extends from the upper fuse terminal 86 and is provided with outturned foot portions 90 to provide latching contact engagement with contact members to be described. The lower contact finger '89 is a horizontal blade-like member and has a head portion 91 at its distal end for contact engagement with a stationary line terminal to be described.

For mounting the fuse 85 on the door 22, brackets 92 are secured, as by bolting, to its inner side for carrying insulators 93. The upper insulator 93 carries a fuse clip 94 for receiving the upper fuse terminal 86. Since the current path to the upper fuse terminal 86 is through the upper contact finger 8 8, it is unnecessary for the fuse clip 94 to be formed of good conducting material since it carries no current. A spring biased latch 95 is rotatably mounted on the fuse clip 94 and is arranged to engage a nut on the upper end of the upper fuse terminal 86 for holding the fuse 85 in position. The lower fuse terminal 87 is provided with a fitting 96 for receiving a book 97 that is carried by the lower insulator 92. It will be understood that other fuse mounting arrangements can be used.

As pointed out, more than one, for example three, fuses 85 can be employed. Associated with each fuse 85 is stationary contact means, shown generally at 100, in FIGS. 6 and 7. The stationary contact means 100 in each instance is mounted on an insulator 101 that is carried by a transverse channel 102 which extends between the side walls 15 and 16 of the metallic housing 12. A terminal pad 103 extends upwardly to permit connection to a bus bar or cable in the top connecting box 11. Also there is provided a terminal pad 104 that permits connection by a cable or bus bar extending upwardly from the bottom connecting box 13.

For interconnecting each fuse 85 and the stationary contact means 100 individual thereto, switch blade means, indicated generally at 105 in FIGS. 6-10, is employed. In FIG. 8 three switch blade means 105 are shown.

The switch blade means 105 are mounted for rotation with an insulator shaft that is indicated, generally, at 106.

The rotatable shaft 106 includes an elongated porcelain insulator 107 having corrugations to increase the creepage distance between the several switch blade means 105 and between them and ground. The poreclain insulator 107 has integral end projections 108. At the left end a cup shaped adapter 109 is joined to the end projection 108 and from it a stub shaft 110 extends into a bearing 111 that is carried by the side wall 15. The switch locking cam 78 is welded to the stub shaft 110.

At the right end of the porcelain insulator 107 a metallic sleeve 114 is secured to the end projection 108. A stub shaft 115 extends from the right end of the metallic sleeve 114 and it is journaled in a bearing, not shown, similar to the bearing 111 and mounted on the side wall 16. An operating arm 116 extends radially from the metallic sleeve 114 for connection to the overcenter spring means 32 in a manner to be described. An L-shaped arm 117 is secured to the metallic sleeve 114 for engaging shock absorber means also to be described.

FIGS. 7 and 8 show the details of construction of each switch blade means 105 which comprises a pair of switch blade members 118 that are formed of fiat copper bars. For mounting the switch blade members 118 on the porcelain insulator 107 to rotate therewith, they are positioned in a metallic tube 119 which is arranged to extend through a transverse opening 120 in the porcelain insulator 107, there being an opening 120 for each switch blade means 105. The assembly is suitably secured in each opening 120 as indicated at 121.

Since it is desirable that the switch blade members 118 have some degree of fiexibility at their ends, they are positioned in juxtaposed relation in the metallic tube 119 and spaced therefrom by spacers 122. Rivets 123 extend through the assembly at one end of the metallic tube 119 and are spaced from the ends of the switch blade members 118.

At the left end of the switch blade members 118, FIG. 7, arcuate interlocking contact members 124 are individually secured by screws 125. The contact members 124 have inwardly extending arcuate flanges 126 that are arranged to engage the outturned foot portions 90 on the respective upper contact finger 88. When the switch blade means 105 occupies the switch closed position, FIG. 6, the interlocking engagement between the upper contact finger 88 and the interlocking contact members 124 is such that, even if it might be possible to move the door handle 26 to unlatch the door 22, it would not be possible to open the door 22. Thus, it is necessary that the switch blade means 105 be rotated to disengage the interlocking contact members 124 from the upper contact fingers 88 to permit opening of the door 22. The arrangement is such that this can take place only when the circuit between the switch blade means 105 and the stationary contact means 100 has been opened.

In order to maintain the interlocking contact members 124 in engagement with the outturned foot portions 90 of the upper contact fingers 88 both electrically and mechanically, leaf springs 127 are employed. As shown in FIG. 7 the leaf springs 127 are bowed at the left end of the metallic tube 119 so as to react between the inner surface thereof and the outer surfaces of the switch blade members 118 adjacent the interlocking contact members 124. The leaf springs 127 extend between the spacers 122 and the switch blade members 118 and are held by the rivets 123.

The other ends of the switch blade members 118 are indicated at 130 and are spaced apart. The end portions 130 are biased toward each other by coil compression springs 131 that react between the outer surfaces of the switch blade members 118 and cup shaped washers 132 that are interconnected by a transverse pin 133. The inner surfaces of the end portions 130 are arranged to have contact engagement with a contact portion 134 of a metallic adapter 135 which forms an integral part of the stationary contact means 100.

It is desirable to effect the disconnection of the switch blade means 105 from the stationary contact means 180 without arcing when the circuit is to be interrupted while carrying current. For this purpose separable contact circuit interrupter means, shown generally at 136, is provided and is mounted on the metallic adapter 135. The separable contact circuit interrupter means 136 can be constructed as generally disclosed in US. Lindell Patent 2,644,878, issued July 7, 1953. It includes a movable contact 137 that, in circuit closed position, is in contact engagement with stationary contact means constituting an extension of the metallic adapter 135. Associated with the movable contact 137 is a trailer 138 of insulation that is arranged to be moved by an operating rod 139 of conducting material for opening the circuit. The operating rod 139 extends through a tubular insulator 140 into which the arc incident to opening of the circuit interrupter means 136 is drawn and confined by it and by the trailer 138. For moving the operating rod 139 through the tubular insulator 148, the former is connected to an arm 141 that is mounted to rotate with an operating shaft 142 which is journaled at its ends in a metallic housing 143 that extends from and is carried by the lower end of the tubular insulator 140. An opening arm 144 is secured to one end of the operating shaft 142 and is arranged to be engaged by an opening cam 145, FIG. 7, that is carried by one of the spaced apart end portions 130 of the switch blade members 119. The opening cam 145 is secured by rivets 146 to the end portion 130. At the other end of the shaft 142 there is secured a closing arm 147 that is arranged to be engaged by a closing cam 148 which is secured by rivets 149 to the other end portion 130 of the switch blade members 118. An exhaust opening 151 is formed in the metallic adapter 135. When the insulator shaft 106, which includes the porcelain insulator 107, is rotated in a clockwise direction as indicated by the arrow 15.2 in FIG. 6, the end portions 130 of the switch blade members 118 move out of contact engagement with the contact portion 134 of the metallic adapter 135 after the opening cam 145 engages the metallic housing 143 to transfer the current path to the circuit interrupter means 136. Thereafter the opening earn 145 engages the opening arm 144. The continued rotation of the shaft 106 in the clockwise direction, as caused by a relatively powerful operating spring to be described, causes the operating rod 139 together with the movable contact 137 to be moved rapidly to the open position to interrupt the circuit and to confine any arcing that may take place within the tubular insulator 140. The length of the arcuate interlocking contact members 124 is such that they do not disengage the outturned foot portions 90 of the upper contact finger 88 until after the circuit has been opened by the separable contact circuit interrupter means 136. In the open circuit positions the arms 144 and 147 occupy the positions shown by the dotted lines and the arm 141, to which the operating rod 139 is attached, is shown by similar means. On reverse rotation of the insulator shaft 106, the arcuate interlocking contact members 124 first have interlocking contact engagement with the outturned foot portions 90 of the upper contact fingers 88. This is followed by engagement of the end portions 130 of the switch blade members 118 with the contact portions 134 of the metallic adapters 135 which form parts of the stationary contacts 100. The circuit is completed when the end portions 130 of the switch blade members 118 make contact with the contact portion 134 of the metallic adapter 135. Since the closing cam 148 has a relatively long cam surface 148', the closing arm 147 is not engaged to rotate the arm 141 and move contact 137 to the circuit closed position until after the circuit has first been completed around the circuit interrupter 136. This arrangement is advantageous when the circuit is closed on a fault as a result of which the current flow may be relatively great and sufficient to damage or destroy the separable contact circuit interrupter 136 should it be closed first. One or more of the fuses blow under these conditions to interrupt the circuit.

As shown in FIG. 6 the head portion 91 of each lower contact finger 89, which is a horizontal blade like member, is arranged to engage a bifurcated end 154- of a stationary line terminal 155 that may be formed by a pair of flat copper bars. The furcations have sufiicient resiliency to make a good contact engagement with the juxtaposed surfaces of the head portion 91 on the lower contact finger 89. The stationary line terminal 155 is mounted on a line terminal pad 156 which is carried by an insulator 157 A transverse channel 158, extending between the side walls 15 and 16, carries the insulator 157. Connection to the line terminal pad 156 can be made by a flexible cable or bus bar extending upwardly from the bottom connecting box 13.

When the door 22 is swung to the open position, the operator can have access to the fuse or fuses 85 for replacing them when necessary. Under these circumstances it is desirable that the arrangement be such that it is impossible for the operator to come into contact with any energized parts within the metallic housing 12. For example, it should be impossible for him to come in contact with any energized part associated with the stationary contact means 100 or with the stationary line terminal 155. In accordance with the invention this safety arrangement is provided employing the construction shown in FIG. 11. Stationary insulating side barriers 159 and 160 are mounted on angles 161 that are secured to the side walls 15 and 16. The insulating side barriers 159 and 160 and the other insulating barriers to be referred to are formed of suitable insulating material. Extending between the guide barriers 159 and 160 is a stationary insulating front barrier 162 that is provided, FIG. 6, with upper and lower openings 163 and 164 through which the upper and lower contact fingers 88 and 89 project. The openings 163 and 164 are of such size and shape that the contact fingers 88 and 89 can be swung therethrough as the door 22 is swung from the fully closed to the open position.

For closing the upper and lower openings 163 and 164 in the stationary insulating front barrier 162 after the contact fingers 88 and 89 have been swung away with the door 22, there is provided a movable insulating barrier or shutter 165. It is slidably mounted by four screws 166 (only two being shown) that are carried by the stationary insulating front barrier 162 and extend through slots 167 in the movable insulating barrier or shutter 165. Upper and lower openings 168 and 169 are provided in the movable insulating barrier or shutter that, as shown in FIGS. 6 and 11, register with the upper and lower openings 163 and 164 in the stationary insulating front barrier 162 when the door 22 is closed.

When the door 22 is swung toward the open position, as shown by broken lines in FIG. 11, the upper and lower contact fingers 88 and 89 are swung through the registering openings 163168 and 164169 and then the insulating barrier or shutter 165 is moved to the position shown by broken lines in FIG. 11. For this purpose a U-shaped member 1'71 is secured to the insulating barrier or shutter 165 for engagement by an upstanding distal end 172 of one arm 173 that forms a part of a bell crank lever indicated, generally, at 174. The bell crank lever 174 is pivoted at 175 on an upper wall 187, FIG. 12, of the cabinet hinge pocket 188. Another arm 176 of the bell crank lever 174 is provided with an arcuate slot 177 which opens at one end into a straight slot 178 for receiving a. pin 159 that is carried by an arm 180, FIG. 12, which is arranged to rotate with a vertical shaft 181. The shaft 181 is square in cross section and extends through inner flanges of the lower hinge extension 24 and thus rotates conjointly with the door 22. The lower end 182 of the vertical shaft or door hinge pin 181 is cylindrical and is journaled at 183 in the bottom wall 19. The upper end of the vertical shaft 181 extends through a cylindrical bearing 184 and is secured thereto by a transverse pin 185. The cylindrical bearing 184 is journaled at 186 in the extension 187 of the bottom wall 19.

The upper hinge extension 23 is journaled on the front wall 14 of the metallic housing 12 in a similar manner. The arrangement is such that the door 22 rotates about a vertical axis which is at right angles to the plane of the horizontal axis about which the shaft 106 rotates that carries the switch blade means 105.

During the initial portion of the rotation of the door 22 from the fully closed position shown in FIG. 11 toward the open position, the pin 179 in the straight slot 178 causes the bell crank level 174 to rotate to the position shown by broken lines. Since the pin 179 rotates with the arm 180 conjointly with the door 22, it moves relative to the straight slot 178 until it reaches the arcuate slot 177. Then continued rotation of the door 22 and the pin 179 causes no further rotation of the bell crank 174 since the pin 179 moves along the arcuate slot 177. When the bell crank 174 has moved to the alternate position shown by broken lines, the insulating barrier or shutter 165 has moved to cover completely the upper and lower openings 163 and 164 in the stationary insulating front barrier 162. As long as the door 22 remains in the open position or in any position in which the pin 179 remains in the arcuate slot 177, the insulating barrier or shutter 165 is locked thereby in the closed position and it is not possible to move it to expose the upper and lower openings 163 and 164 in the stationary insulating barrier 162.

In order to prevent direct exposure between the several fuses 85 and between them and adjacent metallic grounded parts, fuse insulating barriers 190 are mounted on the inside of the door 22 as shown in FIG. 11. They are arranged to swing to the open position with the door 22 and, in the closed position, certain of them are arranged to be juxtaposed to barrier extensions 191 on the movable insulating barrier or shutter 165.

Interphase barriers 192, FIGS. 6 and 11, are provided between the adjacent switch blade means 105. As shown in FIG. 11 they extend rearwardly from the stationary insulating front barrier 162 from locations between furring strips 193 mounted thereon. There are also provided an upper interphase barrier 194 and a lower interphase barrier 195 on opposite sides of the intermediate switch blade means 105. To facilitate application and removal of the lower interphase barrier 195, it is pivoted on a transverse rod 196 that extends between the side walls 15 and 16, a slotted arrangement being provided to permit application and rem-oval of the barrier 195 to and from the rod 196. Each set of interphase barriers 192, 194 and 195 defines an opening 197, FIG. 6, for surrounding the porcelain insulator between adjacent corrugations as seen in FIG. 8.

It is desirable to dissipate the kinetic energy remaining after sufficient energy has been used to rotate the switch blade means 105 to the open position shown in FIG. 13. For this purpose there is provided a dashpot 201 that is secured to a plate 202 which is carried by a mounting bracket 203 carried by the side wall 16. A piston 204 is slidable in the dashpot 201 and has a piston rod 205 extending outwardly therefrom. A return spring 206 is interposed between the piston rod 205 and the dashpot 201 for the purpose of biasing the piston 204 to the right end of the dashpot 201 and to absorb with the air in the dashpot 201 the remaining kinetic energy incident to movement of the switch blade means 105 to the open position. Rotatably mounted on the stub shaft 115 is a dashpot arm 207 that is arranged to engage the right end of the piston rod 205. A stop pin 208, carried by the mounting bracket 203, limits the movement of the dashpot arm 207 under the influence of the return spring 206. The dashpot arm 207 is arranged to be engaged by a foot portion 117' of the L-shaped arm 117 that is secured, as shown in FIG. 8, to rotate with the shaft 106 carrying the switch blade means 105.

For rotating the insulator shaft 106 and thereby the switch blade means from and to the open position, the operating arm 116 that is secured to the metallic sleeve 114 which forms an integral part of the shaft 106 is connected, FIG. 13, by an adjustable link 211 to a switch operating or drive lever 212, FIG. 22. For arresting movement of the switch blade means 105 in a closing direction and in the fully closed position, the switch operating or drive lever 212 is provided with a stop arm 213 that is arranged to engage a stop 214 formed of impact material that is mounted on the bottom 216 of the housing for the recessed operating mechanism support 31. In FIG. 13 the position of the switch operating or drive lever 212 in the closed position is shown by broken lines. In this position the adjustable link 211 and the switch operating or drive lever 212 is in a toggle or slightly overcenter position, thereby insuring that the switch blade means 105 will remain in the fully closed position until the switch operating or drive lever 212 is rotated to break the toggle.

FIGS. 14-23 show the overcenter spring means 32 and certain details of its construction. As pointed out, the housing forming the recessed operating mechanism support 31 includes the bottom 216 of sheet metal having outwardly curved ends and side walls 217 and 218. In FIG. 14 it will be observed that the manually operable handle 33 is secured to an operating shaft 219 the ends of which are journaled in bearings 220 carried by the side walls 217-218. The manually operable handle 33 is secured to the operating shaft 219 through the agency of a spacer sleeve 221 that is fastened by a drive pin 222 to the shaft 219. At the right end of the operating shaft 219 a spacer sleeve 223 is secured by a drive pin 224 thereto. Secured to the spacer sleeve 223 is a mechanism cam 225, also shown in FIG. 19. A hearing washer 226 is interposed between the right end of the spacer sleeve 221 and a hollow shaft 227 that is journaled by needle hearings 228 for free rotation on the shaft 219. Rotatably mounted on the left end of the hollow shaft 227 is a sleeve 229 to which the switch operating or drive lever 212 is secured for conjoint rotation. A pivot pin 230, carried by the switch operating or drive lever 212, serves as a connection to one end of the adjustable link 211, FIG. 13.

Provision is made for rotating the hollow shaft 227 by a spring. For this purpose a mechanism toggle lever 231, FIG. 18, is secured to the right end of the hollow shaft 227 and it carries a pin 232 for connecting it to a bifurcated end 233, FIG. 15, of a spring operating tube 234. The spring operating tube 234 extends rearwardly through the bottom 216 of the recessed operating mechanism support 31 and through a spring housin extension 235 secured to the bottom 216. At the remote end the spring operating tube 234 extends through a fulcrum sleeve 236 which has a knife edge 237 that engages the end 238 of the spring housing extension 235. A coil compression spring 239 surrounds the spring operating tube 234 and it reacts between the fulcrum sleeve 236 and a stop ring 240 that is secured to the spring operating tube 234. In the discharged position of the coil compression spring 239, it and the spring operating tube 234 occupy either the position shown in FIG. 15 or an alternate position in the lower part of the spring housing extension 235 that is symmetrical with respect to the position here shown. The coil compression spring 239 is charged by rotating the mechanism toggle lever 231 to a central position in which a line interconnecting the axis of shaft 219 and the knife edge 237 passes through the axis of pin 232. The coil compression spring 239 is discharged to effect operation of the switch blade means 105 when the axis of the pin 232 moves past this line.

In order to rotate the mechanism toggle lever 231 to charge the spring 239, a rectangular operating pin 244 is provided on and extends laterally from the mechanism toggle lever 231. The operating pin 244 is arranged to be engaged by a shoulder 245, FIG. 19, of the mechanism cam 225 to charge the spring 239 for operating the switch blade means 105 to the switch closed position. Another shoulder 246 is provided on the mechanism cam 225 for engaging the operating pin 244 to charge the spring 239 and effect movement of the switch blade means 105 to the open position. It will be recalled that the mechanism cam 225 is secured for rotation to the shaft 219 to which the manually operable handle 33 also is secured for conjoint rotation.

In order to transmit the force of the coil compression spring 239 for operating the switch operating or drive lever 212, in turn to rotate the shaft 106 and the switch blade means 105, a switch operating member 247, FIG. 23, is secured to the hollow shaft 227 for conjoint rotation therewith. The switch operating member 247 then rotates conjointly with the mechanism toggle lever 231. Switch closing and switch opening arms 248 and 249 extend from the switch operating member 247 and are arranged to engage, respectively, impact members 250 and 251 that are carried by an angle member 252 which is secured to the switch operating or drive lever 212. The switch closing arm 248 engages the impact member 250 for rotating the switch operating or drive lever 212 to move the switch blade means 105 to the closed position while the switch opening arm 249 at the other end of the switch operating member 247 is arranged to engage the impact member 251 to rotate the switch operating or drive lever 212 in the opposite direction to move the switch blade means 105 to the open posit-ion.

It is desirable that means be provided for indicating the various positions of the switch operating or drive lever 212 and thereby the position of the switch blade means 105, and the position of the mechanism toggle lever 231 and thereby indicating whether the coil compression spring 239 is charged or discharged. For this purpose an arcuate position indicator 253 is employed. It is shown in detail in FIG. 17. The arcuate position indicator 253 includes a semicircular central portion 254 for application to the hollow shaft 227. It is secured in frictional engagement therewith by a semi-circular clamp 255 which is held in place by screws 256. This construction permits the arcuate position indicator 253 to be rotated relative to the hollow shaft 227. The periphery of the arcuate position indicator 253, bearing suitable indicia, is visible through a window 257, FIG. 1, in a cover 258 that is secured to the bottom 216 by screws 259.

For operating the arcuate position indicator 253 in accordance with the position of the switch operating or drive lever 212, it is provided with a relatively short arcuate slot 262 for receiving an indicator operating pin 263 that extends laterally from an arm 264 of the switch operating or drive lever 212. The position indicator 253 also is provided with a relatively long arcuate slot 265 for receiving an outturned end 266 of an indicator operator arm 267 which is carried by the mechanism toggle lever 231, FIG. 18.

In order to prevent operation of the manually operable handle 33 under normal operating conditions when the coil compression spring 239 is fully charged, stop lever 270, FIG. 20, is employed. As shown in FIG. 14 the stop lever 270 is rotatably mounted by a pin 271 which extends from the wall 218. A torsion spring 272 acts to bias the stop lever 270 in a counterclockwise direction as viewed in FIG. 15. The stop lever 270 carries a roller 273 that is arranged to engage the periphery 274 of the mechanism toggle lever 231, FIG. 18, and is held in such engagement by the torsion spring 272. The mechanism toggle lever 231 has shoulders 275 and 276 which are engaged by the roller 273 when the coil compression spring 239 occupies one or the other of the overcenter positions to which it is operated by the manually operable handle 33 for ultimately effecting operation of the switch blade means 105 from one position to the other. As long as the roller 273 engages the periphery 274 of the mechanism toggle lever 231 and is out of 12 i engagement with either of the shoulders 275 or 276, the stop lever 270 is held in the position shown in FIG. 15 where a rectangular stop pm 277 carried thereby is out of the path of either of shoulders 278 or 279 that are carried by the mechanism cam 125, FIG. 19. When the roller 273 on the stop lever 270 is permitted to rotate under the influence of the torsion spring 272 into engagement with one or the other of the shoulders 275 or 276, the pin 277 is moved into the path of one or the other of the shoulders 278 or 279 on the mechanism cam 225 which is secured to rotate with the manually operable handle 33. It is prevented from being rotated while one or the other of these conditions obtains.

There may be certain instances where it is desirable that the stop lever 270 be manually released to permit the coil compression spring 239 to be discharged. Such a condition might occur when the switch blade means occupy the open position with the coil compression spring 239 in the overcenter charged position ready to be released for operating the switch blade means 105 to the closed position. For this purpose a tail piece 280 extends from the stop lever 270- and is arranged to be engaged by a push button 281, FIG. 15, that is slidably mounted in a socket 282 which is carried by the cover 258. A spring 283 reacts against the push button 281 to hold it in the non-operated position. A rotatable cover 284 is provided for preventing access to the pus-h button 281 except by authorized personnel. Preferably a key operated lock (not shown) is employed to prevent rotation of the cover 284 from the closed position.

In order to latch the switch blade means 105 in either the closed or the open position, the switch operating or drive lever 212, which is connected by the adjustable link 211 thereto, is provided with a latch pin 286 that extends laterally from the stop arm 213. FIGS. 13 and 21 show by full lines the position of the switch operating drive lever 212 when the switch blade means 105 occupies the open position. Upper and lower latc'h levers 287 and 288 are pivoted at 289 and 290 on the inner side of the bottom 216 and are provided with latch hooks 291 and 292. Torsion springs 293 and 294 act to bias the upper and lower latch levers 287 and 288, respectively, to the latched position. The other ends 295 and 296 of the upper and lower latch levers 287 and 288 are arranged to be operated by a closing armature 297 and an opening armature 298, respectively, under the control of a closing coil 299 and an opening coil 300. It will be understood that suitable remotely controlled circuits are provided for selectively energizing the coils 299 and 300 for effecting operation of the armatures 297 and 298, in turn, to rotate the latch levers 287 and 288 to the unlatched positions.

In addition to the coils 299 and 300, closing and opening push buttons 301 and 302, FIG. 21, are arranged for manual movement of the armatures 297 and 298, respectively. The push buttons 301 and 302 are slidably mounted in sockets 303 and 304 which are carried by the cover 258. Springs 305 and 306 in the sockets 303 and 304 act to bias the push buttons 301 and 302 to the nonoperated positions.

The operation of the overcenter spring means 32 will be described in conjunction with the illustrations in FIGS. 14-21 which show certain relative positions of various parts as viewed from left to right of FIG. 14.

FIGS. 15, 24 and 25 illustrate the relationships when the switch blade means 105 is open 'and the coil spring 239 is discharged. :In FIG. 24 a portion of the manually operable handle 38 is shown by full lines. It will be recalled that it is connected to the mechanism cam 225 to rotate it. -In order to charge the spring 239 for closing the switch blade means 105, the handle 33 is rotated in a counterclockwise direction carrying with it the mechanism cam 225. In FIG. 24 the manually operable handle 33 has been rotated to the broken line position through about 45 from the fully open lowermost posi- 

